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Question
A force of 10 N acts on a body of mass 2 kg for 3 s, initially at rest. Calculate : Change in momentum of the body.
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Solution
Force, F = 10 N
Mass, m = 2 kg
Time, t = 3 s
Initial velocity, u = 0 m/s.
Change in momentum = Final momentum - initial momentum
Δp = mv - mu.
Or, Δp = m (v - u).
Or, Δp = 2 (15 - 0) = 30 kg m/s-1
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